NAME

File::Append::Undoable - Append string to a file, with undo support

VERSION

version 0.01

SEE ALSO

Rinci::Transaction

DESCRIPTION

This module has Rinci metadata.

FUNCTIONS

None are exported by default, but they are exportable.

append(%args) -> [status, msg, result, meta]

Append string to a file, with undo support.

On do, will trash file, copy it to original location (with the same permission and ownership as the original) and append the string to the end of file. On undo will trash the new file and untrash the original.

Some notes:

• Chown will not be done if we are not running as root.

• Symlink is currently not permitted.

• Since transaction requires the function to be idempotent, in the check_state phase the function will check if the string has been appended. It will refuse to append the same string twice.

• Take care not to use string that are too large, as the string, being a function parameter, is entered into the transaction table.

Fixed state: file exists and string has been appended to end of file.

Fixable state: file exists and string has not been appended to end of file.

Unfixable state: file does not exist or path is not a regular file (directory and symlink included).

This function is idempotent (repeated invocations with same arguments has the same effect as single invocation). This function supports transactions.

Arguments ('*' denotes required arguments):

• path* => str

  The file to append.

• string* => any

  The string to append to file.

Special arguments:

• -tx_action => str

  For more information on transaction, see Rinci::Transaction.

• -tx_action_id => str

  For more information on transaction, see Rinci::Transaction.

• -tx_recovery => str

  For more information on transaction, see Rinci::Transaction.

• -tx_rollback => str

  For more information on transaction, see Rinci::Transaction.

• -tx_v => str

  For more information on transaction, see Rinci::Transaction.

Return value:

Returns an enveloped result (an array). First element (status) is an integer containing HTTP status code (200 means OK, 4xx caller error, 5xx function error). Second element (msg) is a string containing error message, or 'OK' if status is 200. Third element (result) is optional, the actual result. Fourth element (meta) is called result metadata and is optional, a hash that contains extra information.

AUTHOR

Steven Haryanto <stevenharyanto@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2012 by Steven Haryanto.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.